The speaker begins with a strange, tender image: a heart carried in a basket, kept safe so it won't break, or so it won't make the speaker's eventual burial easier. That second reason is oddly dark, as if feeling less would make death less of a loss. It suggests someone protecting themselves by holding emotion at a distance.
The second stanza widens out from "I" to "we." Money seems to replace real closeness, and people "close hands" and split into "factions," which fits the title's sense of taking sides. The final lines are the most unsettling. Groups turn against the children, against each other, and then simply "away to bed," as though harm is done and everyone goes back to ordinary life.
The mood is cold, wary, and quietly resigned. The poem judging by its imagery seems to link a guarded heart with a divided, self-serving community, and it leaves the reader uneasy about how easily that happens.